Write a function cost that accepts two arguments: $1)$ a shopping list of items, for brevity, each will be a

single character string $($you do not need to validate this$),$ and $2)$ a pricelist, a dictionary whose keys are items and

whose values are the price in dollars for that item. The function then returns the total cost in dollars of the items in

the shopping list. If some item does not occur in the pricelist dictionary, then $$100$ is charged for that item $($see $2^{nd}$

example$).$

$>>>cost({[}^{\text{'}}{A}^{\text{'}},{?}^{\text{'}}{B}^{\text{'}},{?}^{\text{'}}{A}^{\text{'}}],{\{}^{\text{'}}{A}^{\text{'}}$:$10\mathrm{.}0,{?}^{\text{'}}{B}^{\text{'}}$:$5\mathrm{.}0\})\frac{?}{?}$# Each A costs $10,B$ costs $5$

$25\mathrm{.}0$

$>>>cost({[}^{\text{'}}{A}^{\text{'}},{?}^{\text{'}}{B}^{\text{'}},{?}^{\text{'}}{A}^{\text{'}},{?}^{\text{'}}{C}^{\text{'}}],{\{}^{\text{'}}{A}^{\text{'}}$:$10\mathrm{.}0,{?}^{\text{'}}{B}^{\text{'}}$:$5\mathrm{.}0\})\frac{?}{?}$# $C$ not priced $so$ costs $100$